It may also depend on the material and year of manufacture. The Campagnolo spare parts list uses different codes for the carbon and alloy replacements. For the carbon crankset, there seems to be a different code for the power torque (2011+) and ultra-torque (2010) versions too.

The image shown in the previous post looks like the 2011 and later Chorus/Record bolts (which all go into special threaded chainrings). I would expect something like this product from BBB to be more likely to fit the Athena 11 speed carbon crank (there is a good picture here):

I recently bought a set of FC-AT300 bolts for my Centaur Carbon chainset, this part is listed in the 2012 catalogue as being suitable for Athena Carbon 11-speed and all other 10-speed cranksets (with black bolts).